1. Field of the Invention
The present invention relates to an improved sheet slitter-winder that slits a wide sheet of plastic film or paper or the like into a plurality of sheets of a predetermined width and winds each sheet on a core, that shortens the time required between the stopping of the winding when the winding of a sheet is completed and the start of the next winding operation. It particularly relates to a sheet slitter-winder in which the winder that winds the slit sheet includes touch rollers that guide the slit sheet to the rotating core of the winder and are in contact wilt the peripheral surface of the sheet roll formed by the sheet being thus wound around the core.
2. Description of the Prior Art
In a conventional sheet slitter-winder, when the winding of a predetermined amount of the sheet is completed, the winding drive is stopped, a space is opened between the wound roll and the touch rollers and the sheet leading to the roll is cut on the downstream side of the touch rollers. The wound roll is then removed from the roll holder and replaced by a new core, the sheet is gripped between the new core and the touch rollers, an operator uses adhesive tape or the like to stick the leading edge of the sheet to the core, and winding is resumed.
In the winding apparatus disclosed by JP-B HEI 7-80597, when the sheet attached to a wound roll is cut, to prevent the end of the slit sheet being drawn free of the touch rollers and falling, a support frame is provided to hold the sheet. The frame is at a set distance in the normal direction from the point of contact between the touch rollers and the roll and slightly toward the roll, and extends in the width direction of the sheet On the opposite side of the support frame to where the slit sheet is held, a prop frame is provided that extends in the width direction of the sheet and can be moved from a standby position to push a slit sheet toward the support frame. In order to cut widthwise across the slit sheets just downstream of the support frame, there is a blade that can be moved along the support frame. Double-sided adhesive tape is adhered to the surface of the support frame against which the slit sheet is pushed by the prop frame. When the slit sheet attached to the roll is to be cut, it is pushed toward the support frame by the prop frame and the blade is moved to cut the sheet. After the slit sheet is thus cut, the end of the slit sheet on the upstream side is supported by its adhesion to the support frame.
However, the support frame has to be located far enough away from the touch rollers and roll to ensure that the frame does not interfere with the winding operation. This results in the distance between the support frame and the point of contact being quite large. Since the slit sheet is cut along the support frame, the length of the sheet from the touch rollers to the cut point is too long. Moreover, when the slit sheet is placed between the winding core and the touch rollers and the leading edge of the slit sheet is affixed to the core to resume winding, the operator either trims away the excess part of the sheet on the upstream side or, after adhering the end of the slit sheet to the core, slightly separates the core from the touch rollers and rotates it to wind the excess part of the slit sheet onto the core. This is time-consuming and lowers the rate of operation of the winder.
In the invention described by JP-B SHO 63-26053, the touch rollers have a suction mechanism for processing the trailing end of the wound sheet. When the slit sheet is cut across its width by the cutter, the slit sheet on the upstream side is held on the touch rollers by the suction mechanism, enabling the trailing end of the sheet to be efficiently processed. However, the touch rollers have to be hollow to accommodate the suction means, and have to be provided with many suction holes on the peripheral surface that can damage or deform the slit sheets traveling at high speed.
The present invention was accomplished in view of the above, and has as its object to provide a sheet slitter-winder that has a high operating ratio attained by reducing the time and work required to cut a slit sheet attached to a completed roll and adhere the cut end of the sheet on the upstream side to a new core.
Another object is to provide a sheet slitter-winder that attains high productivity by applying adhesive to a core or slit sheet and reducing the time and work required to apply the adhesive.
Another object is to provide a sheet slitter-winder that attains high productivity by reducing the time and work to mount a new core on the core chucks.